Before joining the Supreme Court, Solís had served in the Nicaraguan legislature and as a military leader.

Solís grew up in a wealthy Catholic family and attended the Colegio Centro América in Managua, Nicaragua.

[3] After the revolution in 1979, Solís joined the Sandinista Popular Army and was its representative in the Council of State.

[3] In 1990 when Violeta Chamorro was elected President, defeating the FSLN, Solis was nevertheless re-elected legislator in the National Assembly.

[4] Solis disputed Ortega's claim that violence in the country resulted from a foreign-backed attempted coup, and predicted that unless pro-Ortega paramilitary groups were disarmed, opposition groups would arm as well, eventually leading to civil war,[6] particularly as the country's economic situation deteriorated.