This is certiorari and mandamus filed against the Commissioner of Civil Service, and the Mayor and the Municipal Board of the City of Manila, to. obtain a ruling that petitioner's reinstatement as  police lieutenant of  Manila is obligatory upon the respondent Mayor.

In  1941  Adriano B. Velasquez was a lieutenant  of the Manila police when he was accused, and convicted together with  policeman Federico Barba of the crime of extortion; he began serving his twenty-year sentence on August 18, 1944, but he was liberated by the guerrillas on February 13, 1945; he asked  for reinstatement on March  3, 1945, but the Provost Marshall of the U. S. Army,  then acting" as Chief of Police denied his request;  his subsequent requests for  re-appointment were likewise refused;  then on  August 24,  1948.  Federico Barba  who had been accused and  convicted like herein  petitioner, re-entered the police force; this gave Velasquez some hopes, so in January 1954 he began mandamus proceedings to compel the Mayor to re-appoint him as police  lieutenant,  maintaining the theory that it was the latter's duty to reinstate him under Executive  Order No. 223 dated September 25, 1939, which reads as follows: 

"A person who has served six months  or less in the Philippines Civil Service may be reinstated as a probationer within  a period of one year following  his separation from the service under the former appointment; *  * * and   a  person who has served five years  or more may be reinstated within ten  years from the daite of his separation from the service."

The Manila court of first instance,  and this Court on appeal (G. R. No- L-7730, August 1954)  found the mandamus petition to be without merit, not only because under the terms of said Order,  reinstatement was discretionary, but also because the  said Order did  not apply to him; inasmuch as he had been separated  from the service for cause: his twenty-year sentence.

A few months later,  on December  7,  1954,  Velasquez started this  second  attempt to return to duty; and obviously in an effort  to evade the  doctrine of res judicata "chose a different theory" and included, as new defendants  the Commissioner of Civil Service and the Municipal Boards However, as thev Solicitor General  and the City  Fiscal suggest,  a party may not renew a  litigation by the expedieht of simply joining new parties.  And the controversy here  is the same  as in G. R-  No. L-7730: does  Velasquez have the right to go back to his job?

Our decision, in August said no: he  had no right to compel reinstatement.  It is alleged  however that in this  petition a new issue not squarely debated in the former case is  presently raised: illegality  of petitioner's  separation from his position  as police  lieutenant.  Even if the point had not been  discussed  then,  still" the principle of  res judicata applies,  inasmuch as  the  point  could and should have  been asserted then and  there.  At that time petitioner claimed he should be taken back because he had a right to be reinstated.   He could and should have added i because he had been illegally separated from the service.

The doctrine is, that a final judgment is conclusive not only as to every matter which was offered to sustain the petitioner's claim or demand, but also as to any other ad' missible matter which might  have been offered for that purpose.  Pefialosa vs. Tuason, 22 Phil.,  303, 312; Philippine National Bank vs.  Barreto,  52  Phil., 818, 824,  (See Moran Comments under  section 45 Rule 39.)  The  party is bound by the previous decision, even if his cause "had not been  properly ventilated" by his former counsel who failed to see and develop a pertinent issue.

Of course, this is  not  an implied  admission that  if petitioner's  cause were examined  anew in  the light  of arguments  advanced by his  new counsel, he would have a chance.   Yet it is not necessary to go over the same grounds, considering our views expressed thru Mr.  Justice Labrador in a recent decision: 

"If an employee is illegally  dismissed, he  may conform to  such illegal dismissal or acquiesce therein, or by his inaction and  by sleeping on  his  rights he  may  in law  be  considered  as having abandoned the office to  which  he  is  entitled to be  reinstated. These defenses are valid defenses to an action for reinstatement. * * * 

We hold that in view of the  policy  of the State contained in the law fixing the period of one year within which  actions for quo warranto may be justified,  any.person claiming right to a position in the civil  service should also be required to file his petition for reinstatement within the period of one year, otherwise he is thereby considered as having abandoned his office."  (Unabia vs. City Mayor, supra, p. 253)

According to appellant, he  was removed by the then Acting Chief of Police  on March 3, 1945; but he  applied to the courts  for  reinstatement only in January  1954, after nine  years.  He waited too long.

The Manila  court's order dismissing this  second petition should therefore be  affirmed,  with costs.

Paras, C. J., Padilla,  Reyes,  A., Bautista Angelo, Reyes, J. B. L., and Endencia, JJ., concur.