negligence

n. failure to act as a reasonable person would be expected to act in similar circumstances, failure to exercise due care.
Negligence, if it causes injury to another, can give rise to liability in tort. Negligence is always assessed having regards to the circumstances and to the standard of care which would reasonably be expected of a person in similar circumstances. Everybody has a duty to ensure that their actions do not cause harm to others.

  In their initial court filing, the organic farmers offered several theories to explain why biotech companies should be liable for the crash of the organic canola market. Their claims included negligence for failing to ensure that the GM seeds they manufactured wouldn't contaminate organic farmland, strict liability for allowing the escape of something likely to do damage, nuisance for interfering with the farmers' use of their land, and trespass for the drift of GM canola onto their farms.

gross ~ - between negligence and the intentional act there lies yet another, more serious type of negligence which is called gross negligence — any action or an omission in reckless disregard of the consequences to the safety or property of another.

negligent

adj. When a person fails to exercise the care that a reasonable, prudent person would exercise under the same circumstances, that person is said to be negligent.
  Even if a court has ruled that their lawyer's negligent conduct contributed to their conviction, defendants like Angel Claudio are still required to show that they are innocent in order to have a claim against their lawyer.