Before being appointed as a judge in the town of Anenii Noi by a decree issued in 2005 by then President Vladimir Voronin, Dorel Musteata had worked for almost ten years as a notary official. In 2011 Mr. Musteață took over as the chairman of the Anenii Noi Court, the promotion being signed by then Acting President Marian Lupu. In 2014 he resigned from the post and accepted a seat in the High Council of Magistrates (CSM).

In November 2016 President Nicolae Timofti appointed Dorel Musteata as a judge to the Chisinau Court, effective from 1 January 2017. In October 2017 the General Assembly of Judges elected Mr. Musteață to serve a four-year term in CMS. In July 2018 CMS asked the Parliament to appoint Dorin Musteață as a sitting judge of the Supreme Court of Justice, until his retirement at the age of 65.

On 24 September 2019, during a time of political turbulence, the Chisinau Court of Appeal decided to call an extraordinary assembly of judges from across the country, but two days later CSM issued a resolution stating that there were no reasons for such a meeting. Nonetheless, the gathering took place and voted to disband CMS and elect new members. CMS did not recognize that decision and quietly continued its activities.

On 29 October 2019 a group of justices filed a complaint with the National Anticorruption Center (CNA) against CMS, claiming that the prerogatives of the CMS members were terminated on 27 September 2019. Therefore they asked CNA to hold the CMS chairman - aka Mr. Musteata - accountable for organizing the council’s meetings on 17 and 22 October 2019. The case is still pending investigation at CNA.

Dorel Musteață is a beneficiary of a subsidized apartment in a residential bloc for magistrates in the downtown of the capital (Vasile Alecsandri Street).