The court service is under "unprecedented pressure" and the fair administration of justice is being "severely undermined" by cost-cutting, a union said on Sunday.
Napo, which represents family court and probation staff, said serious concerns have been raised by its members across England and Wales over the six months up to July this year.
They say problems have been caused in magistrates, crown and family courts by the rolling programme of 135 court closures, cuts to legal aid and shrinking budgets for the police, probation and prison services.
Additional problems have also been reported about interpreters, with Napo members saying they are failing to turn up at court and can be under-prepared and under-qualified, getting key information wrong.
Applied Language Solutions has already faced criticism since it won the contract to provide court interpreters, but the Ministry of Justice said it has seen improvements in the past few months.
Napo said a lack of expert reports has also led to inappropriate sentences being used, for example curfews being imposed in domestic violence cases, which leaves victims at risk.
Assistant General Secretary Harry Fletcher said: "A combination of court closures, financial constraint and curtailment of legal aid is having a negative impact on the administration of justice.
"Staff across the country report an increase in delays and adjournments in both family and criminal courts because of reports not being available, defendants not showing up at court - possibly because of court closures meaning greater travelling distances - and the absence of legal aid.
"These pressures are leading to court reports being produced quickly, on the day, and therefore not containing detailed social histories, which impacts on the nature of sentencing.
"It is of concern that staff are reporting that often inappropriate sentences are handed down, such as curfews in domestic violence cases, and that the absence of interpreters is routinely leading to matters being adjourned and often defendants being remanded unnecessarily."
The probation service is facing a 15% reduction in its budget up to 2015, while the CPS will have its funds cut by a quarter, and police forces across the country are being forced to make savings of around 20%. The legal aid budget will also be cut by a third.
Mr Fletcher added: "The Government justifies the cuts and closures on the grounds that it needs to save money. However, increased delays and adjournments, and cases taking longer in both family and criminal courts, will lead to increased costs in the medium and long term.
"It is also impacting on the effectiveness of the court system. It is critical that the administration of justice is fair and that all parties, be they victims, witnesses, children or defendants, are treated properly and have adequate representation. This principle is being severely undermined."
A Ministry of Justice spokesman said: "We are already taking forward reforms which will benefit victims and ensure more offenders are quickly punished with a sentence that fits their crime.
"These include maximising the use of video-link technology, improving the way agencies work together, removing bureaucracy and providing value for money.
"Recent court statistics show that the timeliness of cases dealt with in the courts has remained consistent over time but we want to improve this further."